DE1569963A1 - Process for the bonding of organopolysiloxane elastomer surfaces with organic elastomer surfaces - Google Patents

Description

Munich, aen <£ ( . Junj. 19 * 66

in Gen. VdIm. (HL-No. 52/64) ■ β / ib _R «q _R1

L Fa-DOWCORNWG Corp, 7 1503963 MkflandiMiclUUSAl

DC

Process for bonding organopolysiloxane elastomer surfaces with organic elastomer surfaces

Organopolysiloxane elastomers are known for their release properties and their resistance to bonding with organic polymers. These elastomers are therefore difficult to bond to organic substrates, such as organic elastomers, and numerous primers and methods have already been proposed for this purpose, but they do not show satisfactory results, in particular for the bonding of organopolysiloxane elastomers to neoprene.

The present invention therefore relates to a method for bonding organopolysiloxane elastomers to organic ones Elastomers, especially neoprene. '

The inventive method for bonding organopolysiloxane elastomer surfaces with organic elastomer surfaces is characterized in that at least one of the surfaces to be glued together from a mixture

000842/1421

(A) 20 to 80 wt.% Of an organic isocyanate and

(B) 80 [in each case based on the total weight of (A) and (B)] and 20 wt.% Of a room-temperature curable to elastomers molding composition

is applied to an organopolysiloxane base, then the surfaces are laid apart with the adhesive layer in between and in this sandwich position until it cures the adhesive mixture are held.

Any known organopolysiloxane elastomers which have been cured by bleaching processes can be used for the organopolysiloxane elastomer surfaces, that is, the elastomers can be in any solid or foam form.

For the organic elastomer surfaces, any natural or synthetic types of rubber are used, e.g., natural rubber such as balata, gutta-percha, and hevea; Butadiene-styrene copolymers, butadiene-acrylonitrile copolymers, Isobutylene-diolefin copolymers, alkylene polysulphides, polychloroprenes (under the name "Neoprene" in trade), nitrile rubber, polyisoprene rubber, Acrylate rubber, such as polyethyl acrylate, copolymers of ethyl acrylate and 2-chloroethyl vinyl ether and mixed poly

009842/1421

merizates of acrylates and acrylonitrile, polyester rubber, such as copolymers of polyesters, for example ethylene glycol, 1,2-propylene glycol or 1,4-butanediol and adipic acid and di isocyanates, for example 1,5-naphthyl endii soeyanat and mixed .. polymers of Polyester amides, such as copolymers. of ethylene glycol, monoethanolamine and adipic acid and, diisocyanates, for example hexamethylene diisocyanate; rubber

chlorinated polyethylene through implementation

with sulfur dioxide and then with metal oxides, accelerators and organic acids (under the name "Hypalon ^ SpS" in trade, manufacturer: du Pont); Rubber made ^ from ^ a plasticized copolymer of vinylidene chloride (under the name "Saran" in trade, manufacturer: The Dow Chemical Company), mixed polymers of butadiene and vinyl pyridine and rubber made from 1H, 1H-perfluoroalkyl acrylates.

Although any organic elastomer with organopolysiloxane elastomers can be glued, the particular advantage of the inventive method is that such organic Elastomers such as neoprene, which previously could only be bonded with organopolysiloxanes with great difficulty, are now very much can be easily connected to it.

Organic isocyanates can be used for the adhesive mixture (A) any mono-, di- and tri-isocyanates, as well as polymers

BATH ORIGINAL

009842/1421

Isocyanates can be used. Specific examples of these are toluene-2,4-diisocyanate, toluene-2,6-diisocyanate, m-phenylene diisocyanate, 4-chloro-1, 5-pheny, Len-diisocyanate, 4,4'-biphenyl diisocyanate, 1,5 -Naphthylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,10-decamethylene diisocyanate, 1,4-cyclohexylene diisocyanate, diphenylmethane-4,4'-diisocyanate, ethylene diisocyanate, ethylidene diisocyanate, propylene-1,2-diisocyanate, cyclo hexylene-1,2-diisocyanate, 3,2 ^f -dimethylbiphenylene-4,4'-diisocyanate, 3, y -dimethoxybiphenylene-4,4'-diisocyanate, 5 * 3'-diphenylbiphenylene-4,4'-diisocyanate, 3 >3'-dichlorobiphenylene-4,4 ^f diisocyanate, triphenylene-ρ, ρ ', p "-triisocyanate, purfurylidene diisocyanate, benzene triisocyanate, hexane ~ l, 2,6-triisocyanate, (O = C = N) ₂ - ^ - / "CH ₂ - / -V (N = C = O) ₂ , benzene isocyanate, butane isocyanate, adducts of polyisocyanates with alcohols which still contain free isocyanate groups, such as trimethylolpropane, glycerol, hexanetriol, glycols or lower polyesters such as castor oil, reaction products of excess diisocyanate with m honest alcohols, e.g. the formulas

HO OH, OH

0 = C = N- / ~ ^ -N-C0CH ₂ CH ₂ 0C-N- / ~ AN = C = 0 and C (CH ₂ OC-N - / ^ S-CH,)

^ Ti = C = O

polymeric organic isocyanates that contain unreacted isocyanate groups contain, organosilicon isocyanates in which the isocyanate groups are attached to organic radicals, e.g.

of the formulas

0 098 42 / 1A 21 bad original

(O = C = N-CH ₂ CH ₂ OCH ₂ CH ₂ CH ₂ Si) ₂ 0, Si [OSi (CH ₂ J ₁₁ N = C = C

CH ₃

Also isocyanates according to U.S. Patent Nos. 3.170.89I and Isocyanates of the formulas

H 0 (CH ₃ J ₂ (CR ₅ I ₂ OH O = C = NC ₆ H ₁₂ N-COCH ₂ CH ₂ Si - / "" N-SiCH ₂ CH ₂ OC-NC ₆ H ₁₂ N = C = O and

C ₆ H ₅ CH, OH
C ₆ H ₅ Si [OSi-CH ₂ CHO-CN- ^ VcH,], and others according to

CH, N = C = O

U.S. Patent No. 3,179 x 622, and isocyanates of the formulas

HO V ^ 3 CHN-COCH ₂ Si - [OSi] _x - OSi (CH ₂ OC-N

I ₂ -CH ₂

CH ₂ -CH ₂

CH ,. ^ * CHN = C = 0) ₂ , where χ is an integer,

CH ₂ -CH ₂ "

The isocyanates listed are known, and most of them are commercially available products. Preferably organic

Isocyanates with an average of at least 2 isocyanate groups used per molecule. 009942/1421

The organopolysiloxane-based molding compositions (B) which cure at room temperature to give elastomers are also known and can be so-called one-component compositions or two-component compositions, the one-component compositions being preferred . Such molding compounds are, for example, in US Patents No. 5.O35.OI6, 3.O6I.575, 3.O77.465, 3.IO9.OI3, 2.833.742 and German Patent Nos. 1.104.176, I.171.615, 1,166,469, I.I63.540 and 1,155,592 .

A particularly preferred adhesive mixture is a composition of diphenyl methane-4,4'-diisocyanate and a molding compound which can be hardened to form elastomers at room temperature and which consists essentially of a dimethylpolysiloxane having terminal hydroxyl groups, a silicon dioxide filler and monomethyltriacetoxysilane.

When carrying out the process according to the invention, the two components (A) and (B) are first mixed with one another in the stated proportions. Preferably 20 to 40 wt.% Of component (A) with 60 to 80 wt.% Of component (B), each based on the total weight of (A) and (B), vigorously mixed using conventional mixing devices, advantageously in the absence is worked by moisture, and the mixture is then stored in the absence of moisture. When the finished mixture is shortened

Time to be used is working under

009842/1421 _0BlcaNW .

However, exclusion of moisture is not absolutely necessary. The finished mixture is then applied either to the surface of the organopolysiloxane elastomer or the surface of the organic elastomer or to both surfaces, which can be carried out by conventional methods such as spraying, dipping or calendering . The surface coated with the adhesive mixture is then placed on top of one another with the uncoated surface in such a way that the adhesive mixture is located between them. The decisive factor here is that the two surfaces placed one on top of the other are made of different materials. When both the organopolysiloxane elastomer surface and the surface of the organic elastomer are coated, the two coated surfaces are placed on top of one another. After the surfaces have been laid on top of one another, they are left in this position until the adhesive mixture has hardened to form a solid elastomeric material. For the cohesion of the surfaces with the adhesive layer in between in sandwich or laminate form , an external force can be applied, for example by clips, by hand or by gravity. However, some of the bonding mixtures are sufficiently adhesive that the two surfaces are held together even without the application of external force.

BATH ORIGINAL

0Q98A27U21

For those bonded by the method according to the invention Shaped bodies, which consist essentially of an organopolysiloxane elastomer and an organic elastomer, plays the structure and shape of the two elastomers do not play a decisive role. Of course, the two surfaces must adjoin each other so that they can be glued. The required amount of adhesive is also required not critical, that is, any amount that is economically feasible can be used. The Verkleungsmi Schung itself is elastic, so that large and small amounts of it can be used. Irregular too Surfaces can be glued together, as the irregular areas with the adhesive mixture, which becomes elastic after hardening, can be filled.

The advantage of the method according to the invention consists in First and foremost, the fact that with it numerous organic elastomers, in particular neoprene with organopolysiloxane elastomers can be glued, which has so far only been unsatisfactory. Gluing can be done at room temperature can be carried out without the use of pressure or other special equipment. Though for making the glued elastomers do not require any special devices are required, the use of the same is not excluded. So can the organopolysiloxane elastomers and the organic elastomers with the inventive

0098A2 / U21 bad

Bonding mixture can advantageously be connected under pressure and heating to temperatures of up to 300 ° C. the .These measures ensure the strength of the bond increased, and the curing time of the adhesive mixture is considerably reduced as a result.

The sandwich structures bonded by the method according to the invention can be used on rollers, that come into contact with hot material, e.g. for rollers that are used to apply hot plastics Paper, steel and the like are used for coating will. In such rolls, the outer surface consists of the organopolysiloxane elastomer, which is particularly is heat-resistant, does not become brittle over time, and to which hot plastics do not adhere. The sandwich structures can be used with success wherever separability and heat resistance of a surface is required.

example 1

A Verklebungsmisehung was by vigorous mixing of the following ingredients was prepared: J50% by weight of 4,4'-diphenyl met hand.! i socyanate (31.3 wt. ^ Isoeyanatgruppen) and 70 wt. % of a curable at room temperature to give elastomers

009842/1421.

Molding compositions composed of the following ingredients: 100 parts by weight of one having hydroxyl groups in the terminal units Dimethylpolysiloxane with a viscosity of about 4000 cSt / 25 ° C, 31.5 parts by weight of one with trimethylsiloxy groups modified silica, 40 parts by weight of one having hydroxyl groups in the terminal units Dimethylpolysiloxane with a viscosity of 1000 cSt / 25 ° C, 6 parts by weight of titanium dioxide and 9.25 parts by weight Monomethyltriacetoxysilane. The bond mix was uniform across the surface at a thickness of about 0.089 cm sprayed on a neoprene sheet. A cured dimethylpolysiloxane elastomeric film was then placed over the bond mix placed. The sandwich was pressed firmly together by hand and then at room temperature for 16 hours left to cure the bonding mixture. The bond strength was determined by a peel test according to Military Specification, "Cement: General Purpose Synthetic Base", MIL-C-4003 (USAP) 5 October 1949, paragraph 4.5.1.1 certainly. The samples were tested by pulling a strip at an angle of 180 °. A test device, e.g. a Scott tester with a jaw separation rate of 50 cm per minute was used. The first and last 2.5 cm of the test strip were not used. The average adhesion was 0.57 kg / cm certainly.

009842/1421

Example 2

A cured Dimethylpalysiloxanelastomer was bonded to neoprene, as described in Example 1, except that the Verklebungsmischung from 33 * was 3 wt.% Diisocyanate and 66.7 wt. ^ Of the curable to elastomers at room temperature molding composition. The adhesion was equivalent to that obtained in Example 1.

Example 3 '

By using the following adhesive mixtures for gluing of a cured dimethylpolysiloxane elastomer with neoprene were used in that described in Example 1 Test method obtained practically the same results:

A. 20 parts by weight Toluene-2,4-diisocyanate,

80 parts by weight an organopolysiloxane molding compound curable at room temperature to give elastomers the average formula

CH ₃

iOi (CH,) ₂ SiO] ₁₆₂ Si (OOCCH,

B. 25 parts by weight 1,4-tetramethylene diisocyanate, 75 parts by weight one at room temperature to elastomers

curable organopolysiloxane molding compound OBIGEM- the average sfcrmei

DQ8842 / U21

1589963

CH ₃

C. 50 parts by weight 1,5-naphthylene diisoeyanate,

Parts by weight a curable to elastomers at room temperature molding composition comprising a mixture of 100 parts by weight of hydroxyl groups in the terminal units dimethylpolysiloxane having a viscosity of 10,000 cSt / 25 ⁰ C, 10 parts by weight Methyltriacetoxysllane, 40 parts by weight of a dimethylpolysiloxane end-blocked with trimethylsiloxy groups and having a viscosity of 1000 cSt / 25 ° C., parts by weight. of a pyrogenic silicon dioxide obtained in the gas phase and 0.25 parts by weight Dibutyl tin diacetate.

D. 60 parts by weight of a partially polymerized 1,4-cyclo-

hexylendiisocyanafcs with 25 wt.% of isocyanate groups,

Parts by weight an organopolysiloxane molding compound curable at room temperature to give elastomers the average formula

00984271421

(CH ^ COO) ₅ SiCaa ₂ CH ₂ SiO [(CH ^) ₂ SiO] ₅₂₀ SlCH ₂ CH ₂ Si (OQCCH,),

E. 55 parts by weight of propylene-1 ^ -diisocyanate,

Parts by weight one at room temperature to elastomers curable molding compound from a mixture of 100 parts by weight of a semi-solid dimethyl polysiloxane, 4θ parts by weight of a finely divided silicon dioxide filler 5 parts by weight of polysilicic acid ethyl ester and 1 part by weight of the condensation product of ethylamine and formaldehyde.

F. 55 parts by weight 5,5-dimethoxybiphenylene-4,4 ^1- diisocyanate,

Parts by weight one curable to elastomers at room temperature Molding compound from a mixture of 100 parts by weight one liquid in the terminal units Dimethylpolysiloxane containing hydroxyl groups with a viscosity of 15.ΟΟΟ cSt / 25 ° C, 50 parts by weight, Diatomaceous earth, 0.5 parts by weight of lead octoate and 1.5 parts by weight of ethyl polysilica.

G. 45 parts by weight Triphenylene-ρ, ρ ', p "-t'riisocyanate,

Parts by weight one curable to elastomers at room temperature Molding composition from 100 parts by weight of a non-flowing benzene-soluble dimethylpolysiloxane, 50 parts by weight of diatomaceous earth, 5 parts by weight of one

O09842 / 1A21

from volatiles freed from polysilicic acid ethyl ester and 0.5 öew. Parts of dibutyltin diacetate.

H. 5 parts by weight Butane isocyanate,

Parts by weight of the isocyanate of the formula

Parts by weight a molding compound composed of 100 parts by weight and curable at room temperature to give elastomers of a semi-solid dimethylpolysiloxane, 68 parts by weight of diatomaceous earth, 2 parts by weight a mixture of 1 part by weight of dibutyltin dilaurate and 5 parts by weight of ethyl polysilica.

I. 70 parts by weight of the adduct of furfurylidene diisocyanate and

Trimethylolpropane,
Parts by weight one at room temperature to elastomers

curable organopolysiloxane molding compound of Average formula

which is catalyzed with di-n-hexylamine.

009042/1421

Parts by weight of the isocyanate of the formula

HO

IF

Parts by weight one at room temperature to elastomers curable organopolysiloxane molding composition of the average formula

^C 6 ^H 5 Si

CH,

CH

and catalytic amounts of dibutyl tin dilaurate.

K. Ö0 parts by weight of the isocyanate of the formula

(O = C = N-CH ₂ CH ₂ OCH ₂ CH ₂ CH ₂ Si) ₂ O,

Part by weight of a molding compound, curable at room temperature to give elastomers, made from 100 parts by weight of an organopolysiloxane of the average formula (CH ₃ OCH ₂ CH ₂ O) ₃ SiOl (CH, O ₂ SiO] ₇₂₃ Si (OCH ₂ CH ₂ OCH ^) ₃ ,

40 parts by weight of a trimethylsiloxy-terminated dimethylpolysiloxane units a viscosity of 1000 cSt / 25 ⁰ C, 25 parts by weight of a high surface area, Siliciumdioxydxerogels

009842 / H21

_BM3 «*» «« ·

2.5 parts by weight of di-n-hexylamine.

L. 75 parts by weight of the isocyanate of the formula

H 0 (CH,) ₂ (CH,) ₂ OH

t tt t / ~~ \ '" ^r

O = C = NC ₆ H ₁₂ N-COCH ₂ CH ₂ Si - ^^ - SiCH ₂ CH ₂ 0C-NC ₆ H _{l2 NC-} (

Parts by weight a molding composition curable at room temperature to give elastomers from a mixture of 100 parts by weight of a siloxane of the average formula

and 1 part by weight of tetraisopropyl titanate.

M. 60 parts by weight of the isocyanate of the formula

O = C = NCH CHN-COCH ₀ SiOi (CH ^) ₀ SiO].

'CH ₂ -CH ₂

CH ₃ ■ 0 H _{CH CH}

1 ti t ^ y ^ d _t c * - »^
Si (CH ₂ OC-NCH CHN = C = O) ₂

'CH ₂ CH ₂

Parts by weight a molding composition curable at room temperature to give elastomers from a mixture of 100 parts by weight one in the terminal units hydroxyl groups on v; send dimethyl polysiloxane with a Vicko-

0098A2 / U21

- 17 -

sity of 16,500 cSt / 25 ⁰ C / 50 parts by weight of quartz powder and a mixture of 0.5 part by weight of OrtJaokieselsaureätiiylester and 0.2 part by weight of dibutyltin dilaurate.

M. 10 parts by weight Toluene-2,6-diisocyanate,

Parts by weight a partially polymerized m-Phenylendiisocyanats with 15 wt.% of isocyanate groups, parts by weight one at room temperature to elastomers

curable molding composition of a mixture of 100 parts by weight of hydroxyl groups in the terminal units dimethylpolysiloxane having a viscosity of 28,000 cSt / 25 ⁰ C, 5 parts by weight Bistriäthoxysiläthan and 2 parts by weight of stannous octoate (28% tin).

0. 20 parts by weight 4,4'-biphenyl diisocyanate,

Parts by weight 1,10-decamethylene diisocyanate, parts by weight a partially polymerized Äthylendiisocyanats with 25 wt.% of isocyanate groups, parts by weight a curable at room temperature to give elastomers molding composition of a mixture of 100 parts by weight of having the terminal units hydroxyl Dirnethylpolysiloxans having a viscosity of 28,000 cSt / 25 ⁰ C, 5 parts by weight PoIyvinyltriäthoxysilari and 2 parts by weight of stannous octoate _BHO orig ^ ^AU (28 % tin).

0O9842 / U21

- 18 -

P. 20 parts by weight Diphenylmethane-4,4 ¹ -diisocyanate, parts by weight a molding composition curable at room temperature to give elastomers from a mixture of 100 parts by weight of a dimethylpolysiloxane with a molecular weight of 500,000, 70 parts by weight of calcined diatomaceous earth, 10 parts by weight of a methylpolysiloxane resin with 5% ethoxy groups and 1.5% by weight .-Parts of dibutyltin dilaurate.

Q. 5 parts by weight Ethylidene diisocyanate,

Parts by weight Cyclohexylene-1,2-diisocyanate, parts by weight Benzene triisocyanate,
Parts by weight Benzene isocyanate,
Parts by weight one at room temperature to elastomers

curable molding composition from a mixture of 100 parts by weight of a dimethylpolysiloxane with a viscosity of 300 cSt / 25 ⁰ C, 50 parts by weight of a silicate-containing chalk, 10 parts by weight of phenyltributoxysilane and 5 parts by weight of lead oxide.

R. JO part by weight 3,3'-dimethylbiphenylene-4,4'-diisocyanate, parts by weight a curable to elastomers at room temperature molding composition comprising 100 parts by weight of a mixture of 100 parts by weight of a dimethylpolysiloxane with a viscosity of 3O.OOO cSt / 25 ⁰ C and 50 parts by weight

009842/1421, _, "..

Calcined diatomaceous earth, 100 parts by weight of a framework of 70 parts by weight of polyvinyl chloride, 25 parts by weight of diallyl phthalate and 5 parts by weight of dibutyltin dilaurate and 40 parts by weight of a methyl hydrogen polysiloxane with a viscosity of 150 cSt / 23 ⁰ C.

P. 20 parts by weight]. 3,3 '-Diphenylbiphenylen-4,4 ¹ -diisocyanate, parts by weight 3,3'-dichlorobiphenylene - ^, ^ '- diisocyanate, oO parts by weight one at room temperature to elastomers

curable molding compound from a mixture of 100 parts by weight of e-ir. »s in the terminal units containing hydroxyl groups dimethylpolysiloxane with a viscosity of 21,000 cSt / 25 ⁰ C and 0 ^ 5 Ge \ ·;. $ Si-bonded

Hydroxyl groups and 3 parts by weight of methyltriacetoxysilane.

T. 45 parts by weight of the isocyanate of the formula

O H

rt ι

N = C = O

Parts by weight of the isocyanate of the formula

Si [OSi (GH ..;, 7th K = C = C] ₄

009642/1421

■ · --'- ■ '. ■ - 20 -

Parts by weight one at room temperature to elastomers

curable molding composition from a mixture of 100 parts by weight of a dimethylpolysiloxane having hydroxyl groups in the terminal units. a viscosity of 2000 cSt / 25 ⁰ C, 20 parts by weight of diatomaceous earth, 20 parts by weight of zinc oxide, JO parts by weight of calcined clay, 2 parts by weight of a partially hydrolyzed ethyl orthosilicate, 2 parts by weight of tin octoate in petroleum ether (6 % tin) and 20 parts by weight of a chlorinated polyphenyl product, consisting of a mixture of chlorinated diphenyl, chlorinated terphenyl and chlorinated higher polyphenyl compounds with an average chlorine content of 48 wt. ^.

U. 33 parts by weight Diphenylmethane-4,4 ¹ -diisocyanate, parts by weight a molding compound curable at room temperature to give elastomers from a mixture of 100

Parts by weight of a dimethylpolysiloxane with groups of the formula

CH-

is end-blocked, and has a viscosity of 1200 cSt / 25 ⁰ C and 25 parts by weight of silicon dioxide filler.

009842 / U21

BATH ORIGINAL

Parts by weight of a polymerized diphenylmethane-4., 4 ¹ -diisoeyanats with 5 wt. % Isocyanate groups, parts by weight. an organopolysiloxane molding compound of the average formula curable at room temperature to give elastomers

JoSiO]

BATH

009842 / U21

Claims (1)

Claim; Process for bonding organopolysiloxane elastomer surfaces with organic elastomer surfaces, thereby characterized in that at least one of the surfaces to be glued together consists of a mixture (A) 20 to 100 % by weight of an organic isocyanate and (B) 00 to 20 wt. ^ [In each case based on the total weight of (Aj and (B)] a molding compound curable at room temperature to give elastomers is applied to an organopolysiloxane base, then the surfaces are placed on top of one another with the adhesive layer in between and are held in this sandwich position until the adhesive mixture has hardened. BATH ORIGINAL 009842/1421